Harvests were already starting as much as a 1½ days earlier each year as a result of climate change, he said.

Areas suitable for viticulture could fall by 68 per cent in Mediterranean Europe by 2050, and by 73 per cent in regions of Australia with a Mediterranean climate, according to a study published in the Proceedings of the National Academy of Sciences of the US.

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The authors said New Zealand's vineyard acreage could more than double and it would also surge in northern Europe and western North America.

"As the world heats, Tasmania's very well positioned because of the cooler climate," Mr Dearie said. "We've got out of places like the Hunter; in the longer term I think it will be hot and dry and expensive."

The company sold its vineyards in the Hunter Valley, where the Lindemans brand originated, as part of a shift to more profitable growing regions.

Australia's most prestigious wine award in 2011 went to a shiraz from southern Tasmania, a region better known for cooler climate white wines and pinot noir grapes.

An earlier study, led by CSIRO researcher Leanne Webb, found that just under half of Australia's potential wine country could become unsuitable by 2050, though with the caveat that winemakers could adapt with new techniques and more dense vineyard development in the remaining suitable areas.

Treasury's growers are monitoring growing seasons to update their forecasts of local climate change impacts, and delaying pruning work.

Mr Dearie said Treasury needed to source more high-quality land to meet demand for premium wines and was looking in the United States, Australia and New Zealand.

While the company would also like to find vineyards in France as a means to gain access to the Asian market, prices were too high at present.

"We don't actually have the wine," he said.

"It's a question of making the wine first and then selling ourselves into the market."

The winemaker still has not found the limits of demand for its upmarket wines. It recently increased prices for its 2008 Penfolds Grange to $785 a bottle, a 26 per cent rise, as growing Chinese demand for high-end wines outpaces supply.